Abstract

Single ZnOnanorods with diameters of were grown on Au-coated substrates by catalyst-driven molecular beam epitaxy. Individual nanorods were removed from the substrate and placed between Ohmic contact pads and the current–voltage characteristics measured as a function of temperature and gas ambient. In the temperature range from , the resistivity of nanorods treated in at prior to measurement showed an activation energy of and was insensitive to the ambient used ( or 10% in ). By sharp contrast, the conductivity of nanorods not treated in was sensitive to trace concentrations of gases in the measurement ambient even at room temperature, demonstrating their potential as gas sensors.

Received 27 May 2004Accepted 14 July 2004Published online 17 September 2004

Acknowledgments:

The work at UF is partially supported by AFOSR grant under Grant No. F49620-03-1-0370, by the Army Research Office under Grant No. DAAD19-01-1-0603, the Army Research Laboratory and the National Science Foundation (DMR 0400416, Dr. L. Hess).